Extracting a character string from a document and partitioning the character string into words by inserting space characters where appropriate

Abstract

An apparatus includes a character extraction unit configured to extract a character string from a document including layout information, a character width acquisition unit configured to acquire space character width information, and a spacing amount determination unit configured to determine a spacing amount of each inter-character space based on the character string extracted by the character extraction unit and the layout information. The apparatus further includes an insertion unit configured to determine whether a space character is to be included in each inter-character space based on the spacing amount of each inter-character space determined by the spacing amount determination unit and the space character width information acquired by the character width acquisition unit, and to insert a space character code into an inter-character space in which a space character is determined to be included.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a document processing method and a document processing apparatus, and more particularly to a document processing method and a document processing apparatus for extracting a character string from a document including document layout information.[0003]2. Description of the Related Art[0004]Conventional methods may be used to search a document for a character string by extracting a character string included in the document and determining whether the character string includes a search key. For example, in a general searching method, it is determined whether at least apart of the extracted character string includes a search key (hereinafter referred to as a “normal search”). Specific search examples include an “exact word-match search” for searching for a full-matched word and a “phrase search” for searching for a phrase including a plurality of words including a space or spaces.[0005]For ex...

AI Technical Summary

Benefits of technology

The method improves the accuracy of character string searches by correctly inserting space characters, enabling successful word and phrase searches in documents with layout information, even when spaces are represented by character position changes.

Problems solved by technology

However, the exact word-match search cannot find “the” in the “theory” as a hit.

If characters are extracted from such a PDF document or PDL document, a character code of a space character is not included in the characters, resulting in a problem that neither the exact word-match search nor the phrase search can correctly find a word or phrase.

Also, the exact word-match search cannot find any word.

However, the technique as discussed in Japanese Patent Application Laid-Open No. 5-67237 aims at processing a scanned image, not at processing a document described in character code.

Further, the technique as discussed in Japanese Patent Application Laid-Open No. 5-67237 may not obtain a correct space character width, so that a space determination accuracy is lowered.

In addition, a character image may be erroneously recognized upon character recognition to provide wrong character code as a recognition result.

This causes a problem that the exact word-match search and the phrase search may rarely find a word or phrase as a hit.

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